Message-ID: <3634D8C9.B4DF95E7@clover.c2d.fedex.com>
Date: Mon, 26 Oct 1998 14:17:13 -0600
From: Walter Moore <walter AT clover DOT c2d DOT fedex DOT com>
Organization: Federal Express
X-Sender: "Walter Moore" <walter AT clover DOT c2d DOT fedex DOT com> (Unverified)
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To: "djgpp AT delorie DOT com" <djgpp AT delorie DOT com>
Subject: porting socket based client server from Unix to win95 
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Reply-To: djgpp AT delorie DOT com

Hi all. 

  I thought I'd write a note explaining everything I had to 
do to port client/server programs from UNIX to Win95, using DJGPP,
RSXNTDJ, winsock.h, and wsock32.dll. Note, the project was 
originally compiled with gcc on solaris 2.5.

1. get and install dgjpp, and rsxntdj, 
   use the zip picker found at:
   http://www.delorie.com/djgpp/ 
   you'd need C, C++ and assembler, you can get rhide if you like
   integrated environments, I never used it, though I did install it.
   I did not need the extra documentation formats, as the zip files
   with the binaries had the man pages. You'll DEFINITELY need RSX, 
   so as to be able to use the Win95 wsock32.dll.

   I ended up installing most of the DJGPP software to have a complete 
   unix-like environment (djdev201, djlsr201, djst201, djcrx201, 
   faq210b, rhide11b, binutils, bash, bison, diffutils, fileutils, 
   findutils, fles, gcc, gdb, gpp, grep, awk, gzip, ispell, libg++, 
   less, make, ObjC, path, sed, sh-utils, textutils, rsxntdj), so 
   you might need more than just the stuff before the more complete 
   list.  I also ended up moving all the *.1 *.5n and *.7n
   files from c:\djgpp\info into c:\djgpp\man\man1, man5, and man7,
   renaming the *.5n to *.5 and *.7n to *.7 so man would work better.

   besure to read each readme file that comes with the various
   packages, as there is often something that needs to be added to
   autoexec.bat or c:\djgpp\djgpp.env.

2. get, install and patch the MSSDK headers for use with RSXNTDJ:
   get http://webhome.idirect.com/~eschunk/mssdk/rsxpatch.zip
   unzip rsxpatch.zip (assume to \tmp)
   get
   http://mssjus.www.conxion.com/msdownload/platformsdk/i386/iBLDENV.Exe
   run iBLDENV.Exe (assume to c:\MSSDK)
   copy c:\MSSDK\include\*.* \rsxntdj\include\mssdk 
   copy c:\tmp\patch.exe c:\djgpp\contrib\rsxntdj\include\mssdk
   copy c:\tmp\sdkpatch.dif c:\djgpp\contrib\rsxntdj\include\mssdk
   cd c:\djgpp\contrib\rsxntdj\include\mssdk
   patch<sdkpatch.dif
   copy c:\tmp\specspat.dif c:\djgpp\contrib\rsxntdj\lib

   now patch the original rsxntdj specs file:
   mv patch.exe c:\djgpp\contrib\rsxntdj\lib
   patch<specspat.dif

  if you have problems getting the MicroSoft Software 
  Development Kit, go to http://msdn.microsoft.com/developer/sdk/ 
  to read more about it, or to find its new location. If the site 
  is busy, you can find another site by going to 
  http://www.microsoft.com/msdownload/platformsdk/bldenv.htm
  and  then get and install the Microsoft Software Dev. Kit, so 
  you can use the include directory (you might have to register 
  for this, but its free, I think).

3. You can ensure the changes you make to code is strictly for 
   ths DJGPP compiler by putting those changes between
  #ifdef __DJGPP__
  #endif

4. I had to use <winsock.h> and not use the usual include files
   for networking. Here were my include files:
  
   #ifdef __DJGPP__
   #include 	<winsock.h>
   #else
   #include	<netdb.h>
   #include	<sys/types.h>
   #include	<sys/socket.h>
   #include	<netinet/in.h>
   #include	<arpa/inet.h>
   #endif /* DJGPP */
   #include	<unistd.h>
   #include	<stdio.h>
   #include 	<stdlib.h>
   #include	<errno.h>
   #include	<time.h>
   #include	<string.h>

5. if you used getopt(), you'll need to redefine the following:
   #define getopt _getopt
   #define optarg _optarg
   #define optind _optind

   Along these lines, if you use the 'extern int environ',
   you will have to declare it in the main definition, like:
   main(int argc, char **argv, char **environ)
   and you'll have to pass it to any subroutines, otherwise,
   the compiler will try to link in winmain().
   you may also have to #define environ _environ (although since
   I did the above definition of main, it was not necessary).

6. If you used read() and write(), and declared the sockets as int, 
   you'll have to change declarations of sockets from int to SOCKET, 
   and change all error checking of sockets from -1 or < 0 to check 
   for INVALID_SOCKET:
   check bind() result for SOCKET_ERROR, rather than <0
   check accept() result for INVALID_SOCKET rather than -1
   check socket() result for INVALID_SOCKET rather than -1
   check connect() result for SOCKET_ERROR rather than -1

   and define these in a header:
   #define read(sock,buf,len) recv(sock,(LPSTR)buf,len,0)
   #define write(sock,buf,len) send(sock,buf,len,0)

7. start MS Windows' socket API at beginning of main():
   
  #ifdef __DJGPP__
    /****************************************************************/
    /* Lets let the Windows Socket API startup,                     */
    /* telling it we want Winsock 1.1.                              */
    /****************************************************************/
    WSADATA wsaData;
    if (WSAStartup(MAKEWORD(1,1), &wsaData) != 0) {
        return 255;
    }
  #endif
 
8. Shutdown the MS Windows' socket API at end of main():

  #ifdef __DJGPP__
    /****************************************************************/
    /* Lets let the Windows Socket API cleanup.                     */
    /****************************************************************/
    
    /* blocking call ? */
    if (WSAIsBlocking())  {
          WSACancelBlockingCall (); 
    }
    WSACleanup (); 
  #endif

9. Using the makelib that came with rsxntdj:
   makelib /windows/system/wsock32.dll -o wsock32.a
   mv wsock32.a libwsock32.a

10. be sure to compile with the -Zwin32 flag and link with 
   the -I. lwsock32 flags, ensuring the right things are compiled 
   and linked in.


Good luck!
Walter Moore
-- 
Walter Moore                Sr. Programmer Analyst
Federal Express             wbmoore AT fedex DOT com
2813 Business Park          Memphis TN 38118 USA
work: 901-369-2640          fax: 901-369-3634